Methods: A before-after survey among adults aged 18-50 was conducted using a stratified multistage sampling method in the 22 districts of Tehran city in 2011. All participants were interviewed at two points in time: baseline (before launching the campaign) and follow-up (after the campaign was finished) using a validated instrument. The campaign included an animation clip about periodontal health and disease that was telecasted in a ten-time interval for ten days from five channels of national TV. The instrument included items related to aetiology and signs of gum disease. Knowledge level was determined as sum score of periodontal knowledge and changes in knowledge score was calculated. Chi-square test, Wilcoxon Signed Ranks Test and logistic regression analysis served for statistical analysis.
Results: 791 individuals (mean age: 32.6 years) were interviewed before launching the campaign, 543 of whom responded on the follow-up session. 245 indicated that they had seen the campaign (30%) and the rest reported that they had not. The mean age of the individuals who participated in the follow-up was 33 years. Improvement of the knowledge score was statistically significant in those who had seen the campaign (0.61±0.96) compared to those who had not (0.29±0.85) (P<0.001). In the regression model, the variables significantly predicted improvement of periodontal knowledge score were seeing the campaign (OR=2.20, %95 CI=1.37-3.54), female gender (OR=1.59, %95 CI=1.05-2.43), being in the age group of 25-34 (OR=1.76, %95 CI=1.00-3.08), having higher education (OR=2.34, %95 CI=1.23-4.43) (OR=3.33, %95 CI=1.66-6.64) and having higher baseline knowledge score (OR=0.25, %95CI=0.17-0.36).
Conclusions: The findings of this study demonstrated a positive impact of the TV campaign on Iranian adults' knowledge regarding periodontal health and disease.